Todd's Adventures in Slime World is a side-scrolling platform game for the Atari Lynx, Sega Mega Drive/Genesis, and PC Engine CD video game systems.
Designed by M. Peter Engelbrite, who also created the Lynx classic Gates of Zendocon, and a number of Atari 2600 titles, it is notable for containing an early example of a large-scale multiplayer combat game (the Lynx version allows up to eight people to play against each other), for having extremely varied gameplay, for being a side-scroller with a useful automap system before Super Metroid, and for teasing players with its vast number of secret areas.
Players in Slime World are armed with a water cannon that can be fired at many angles and can kill most enemies in one hit, and they can also cling to and climb most walls, as well as perform high and long jumps. Although nominally an action game, many rooms require excellent knowledge of the player's abilities and can only be navigated in certain ways, frequently giving it an air of a puzzle game.
The design of Slime World is especially unique for its use of carefully moderated levels of danger. A player can sustain ordinary damage from many sources, and it adds up quickly, but there are also common invulnerability shields and pools of water that remove all damage taken when used. But there are also red enemies that, when shot, result in a spray of red slime that can instantly kill even a shielded player, creating circumstances when it is best not to shoot foes.
There is also a type of enemy called a Hidden Snapper, that instantly kills players that step over it. Snappers are often undetectable until triggered, and instantly fatal if set off. Canny players, however, may often detect subtle design cues left in the world by the designer, and safely jump over the lethal spots of ground. Players (usually) have infinite lives to explore the world, but lose all their inventory items and are also sent back to the last checkpoint arrow passed.